Look into supporting Union in Structured configs

[omry]

[omry]

Bouncing to 2.2.

[jieru-hu]

comments from receipe team:

Does this Union support include the new syntax being introduced (eg. TypeA | TypeB) ?

[kandluis]

For context, this is the proposal (https://www.python.org/dev/peps/pep-0604/), which is introduced in Python 3.10 (which is now also made available at Meta).

It's a big readability win. I'd say it's of middle-to-low importance for us, but just checking if it'll work with the support here in hydra. I suspect so since I assume Union[A, B, ...] and A | B | ... will translate to the same underlying code, so might be entirely transparent to you.

Thanks for thinking of this!

[Jasha10]

Yes, it should be possible to support PEP 604 in structured config type hints.